Module frame_support::storage::types

Storage types to build abstraction on storage, they implements storage traits such as StorageMap and others.

Structs

• CountedStorageMap
  A wrapper around a StorageMap and a StorageValue (with the value being u32) to keep track of how many items are in a map, without needing to iterate all the values.
• CountedStorageNMap
  A wrapper around a StorageNMap and a StorageValue (with the value being u32) to keep track of how many items are in a map, without needing to iterate all the values.
• Key
  A type used exclusively by storage maps as their key type.
• OptionQuery
  Implements QueryKindTrait with Query type being Option<_>.
• ResultQuery
  Implements QueryKindTrait with Query type being Result<Value, PalletError>.
• StorageDoubleMap
  A type representing a double map in storage. This structure associates a pair of keys with a value of a specified type stored on-chain.
• StorageMap
  A type representing a map in storage. A storage map is a mapping of keys to values of a given type stored on-chain.
• StorageNMap
  A type representing an NMap in storage. This structure associates an arbitrary number of keys with a value of a specified type stored on-chain.
• StorageValue
  A type representing a value in storage. A storage value is a single value of a given type stored on-chain.
• ValueQuery
  Implements QueryKindTrait with Query type being Value.

Traits

• CountedStorageMapInstance
  The requirement for an instance of CountedStorageMap.
• CountedStorageNMapInstance
  The requirement for an instance of CountedStorageNMap.
• EncodeLikeTuple
  Marker trait to indicate that each element in the tuple encodes like the corresponding element in another tuple.
• HasKeyPrefix
  Trait indicating whether a KeyGenerator has the prefix P.
• HasReversibleKeyPrefix
  Trait indicating whether a ReversibleKeyGenerator has the prefix P.
• KeyGenerator
  A trait that contains the current key as an associated type.
• KeyGeneratorMaxEncodedLen
  The maximum length used by the key in storage.
• QueryKindTrait
  Trait implementing how the storage optional value is converted into the queried type.
• ReversibleKeyGenerator
  A trait that indicates the hashers for the keys generated are all reversible.
• StorageEntryMetadataBuilder
  Build the metadata of a storage.
• TupleToEncodedIter
  Trait to indicate that a tuple can be converted into an iterator of a vector of encoded bytes.

Type Aliases

• Counter
  The numeric counter type.